The invention relates to an electrical plug, comprising a base with connection pins which project from the front thereof and which are connected to conductors of a connection cable by means of terminals on the rear of the base. An insulating cap attached to the rear of the base covers at least one of the terminals and comprises at least one integral pin which projects into an opening extending from the rear to the front of the base. The front of the base includes a recess for a fuse and contacts for the fuse. The rear of the base and the entire insulating cap are enclosed by an injection molded plastic plug body.
A plug of this kind is known from French Patent Specification No. 2,367,359 laid open to public inspection. The insulating cap serves to ensure that no loose wires of the connection cable can project from the plug body, as this would be very dangerous. The integral pin of the insulating cap closes the opening in the base and its end will be visible at the front of the plug after the injection molding of the plug body. It can thus be checked afterwards whether the insulating cap is indeed present in the plug. If this is not the case, the plug should be rejected, but if a plug without insulating cap is accidentally accepted, it will be unsafe in use.